Giving new meaning to the term “flash mob,” the British have invented a new sex craze called “dogging” that mixes sex, exhibitionism, mobs and the Internet.

Dogging combines technology with swinging, cruising and voyeurism. To wit: Crowds big and small watch exhibitionist couples who’ve met on the Net have sex in cars, and sometimes join in.

“Dogging is the broad term used to cover all the sexual outdoor activities that go on,” says the dogging FAQ at After Dark UK Swingers, a popular dogging site. “This can be anything from putting on a show from your car, to a gangbang on a picnic table.”

Dogging appears to be popular and widespread, attracting heterosexual couples and single men and women of all ages, income brackets and backgrounds. Not surprisingly, however, dogging meets tend to attract more men than women.

Dogging is most often practiced in cars at rural parks, lover’s lanes and superstore parking lots. The term dogging has a number of suggested origins, but it probably refers to the “walking the dog” excuse proffered to spouses for an evening’s absence.

Dogging sessions are usually organized through the dozens of dogging sites and message boards that have sprung up in the last couple of years. Photos are exchanged and meetings arranged by e-mail or mobile phone text message.

At the meet, cell phones and text messages are used to confirm meeting places and, crucially, identities. Cameras and videophones are increasingly used to record what goes on.

“Technology is vital and is the main driver (of the dogging phenomenon),” said Richard Byrne, a lecturer at Harper Adams University College in the United Kingdom who produced a survey (PDF) last year that found dogging to be a widespread and growing problem in Britain’s country parks.

Dogging is so prevalent, 60 percent of U.K. country parks are affected by it, Byrne’s report estimated.